Question: $0.905 \times 0.234 = $
Solution: ${0}$ ${9}$ ${0}$ ${5}$ ${0}$ ${2}$ ${3}$ ${4}$ ${\times\vphantom{0}}$ ${.}$ ${.}$ ${0.005}\times {0.004}= {0.000020}$ ${0}$ ${0}\times {0.004}+C{0.00002}= {0.00002}$ ${2}$ ${0.9}\times {0.004}= {0.0036}$ ${6}$ ${0}\times {0.004}+C{0.003}= {0.003}$ ${3}$ ${0.005}\times {0.03}= {0.00015}$ ${5}$ ${0}$ ${0}\times {0.03}+C{0.0001}= {0.0001}$ ${1}$ ${0.9}\times {0.03}= {0.027}$ ${7}$ ${0}\times {0.03}+C{0.02}= {0.02}$ ${2}$ ${0.005}\times {0.2}= {0.0010}$ ${0}$ ${0}$ ${0}$ ${0}\times {0.2}+C{0.001}= {0.001}$ ${1}$ ${0.9}\times {0.2}= {0.18}$ ${8}$ ${0}\times {0.2}+C{0.1}= {0.1}$ ${1}$ ${+\vphantom{0}}$ ${0}$ ${2}$ ${1}$ ${1}$ ${7}$ ${7}$ ${0}$ ${+\vphantom{0}}$ ${0}$ ${2}$ ${1}$ ${1}$ ${7}$ ${7}$ ${0}$ ${+\vphantom{0}}$ ${0}$ ${2}$ ${1}$ ${1}$ ${7}$ ${7}$ ${0}$ ${+\vphantom{0}}$ ${0}$ ${2}$ ${1}$ ${1}$ ${7}$ ${7}$ ${0}$ ${+\vphantom{0}}$ ${0}$ ${2}$ ${1}$ ${1}$ ${7}$ ${7}$ ${0}$ ${+\vphantom{0}}$ ${0}$ ${2}$ ${1}$ ${1}$ ${7}$ ${7}$ ${0}$ ${.}$ The top number has $3$ digits to the right of the decimal. The bottom number has $3$ digits to the right of the decimal. The product has $3+3=6$ digits to the right of the decimal. $0.905 \times 0.234 = 0.211770$